Understanding the Molecular Epidemiology of Community-Acquired Methicillin-Resistant Staphylococcus aureus in Northern Saudi Arabia: A Spotlight on SCCmec and spa Typing.

Background: Methicillin-resistant Staphylococcus aureus (MRSA) is a strain resistant to certain antibiotics, making it difficult to treat. MRSA infections can occur in healthcare settings and in the wider community. The prevalence of MRSA strains has significantly increased in Saudi Arabia over the last 2 decades. Objective: This study investigated the molecular epidemiology of MRSA isolates from patients at Gurayat General Hospital in Northern Saudi Arabia. Methods: Ninety-seven MRSA isolates were collected from patients in 2018-2019. MRSA isolates were subjected to antibiotic susceptibility testing, SCCmec typing, spa typing, and pvl gene detection. Results: All strains were susceptible to vancomycin, teicoplanin, and linezolid. Resistance to clindamycin (33%) and erythromycin (44%) was common. Resistance to ciprofloxacin (19%), gentamicin (14%), and tetracycline (19%) was also observed. Forty-four spa types were identified, with t304 (11.4%), t044 (8.4%), and t0127 (8.4%) being the most common. SCCmec types IVd (39%), IVc (27%), and V (24%) were most frequent. Additionally, the pvl gene was detected in 49% of the isolates. Conclusion: Community-acquired MRSA clones are prevalent in the healthcare setting. The predominant genotype was t304 (10%), followed by t044 (7%) and t0127 (7%). The SCCmec IVd type was the most common type frequently associated with spa type t304, whereas SCCmec type IVc was primarily associated with spa type t044. Isolates harboring SCCmec type IVd showed more nonsusceptible phenotypes to ciprofloxacin than other SCCmec types. Most MRSA isolates were resistant to erythromycin and clindamycin. These findings provide valuable insights into the molecular epidemiology of MRSA in the northern region of Saudi Arabia and highlight the prevalence of specific MRSA strains and their antibiotic resistance profiles. This information is essential for monitoring and addressing the spread of MRSA in healthcare settings.